On Android you will get USB to format to Fat32. This won't allow files of over 4GB.
Since you can't access a PC there are two options. Get a SDXC card and it will be automatically formated to exFat in Android, or if you can get to a Playstation4 it will have the option to format a USB pen into exFat.
Appreciate it, looks like that’s my option for now. I’ll try and get to one of those and get the stick formatted that way.
Thanks